1. Field of the Invention
This invention relates to aquatic harvesters, or machines for harvesting aquatic growth from rivers and lakes and more particularly, to a new and improved rake apparatus or compactor and dual paddle wheel mechanism for redistributing, compacting and unloading aquatic growth which has been harvested and deposited on the deck of the harvester and maneuvering and driving the aquatic harvester, respectively, The compactor includes a carriage fitted with rollers designed to traverse rails on the deck of the harvester by means of a serpentine chain drive system, in order to relocate and compact aquatic growth deposited on the deck by a cutter blade and endless belt harvesting system. The rake further includes multiple, downwardly extending teeth attached to pivot arms in the carriage and raised and lowered by means of hydraulic cylinders to selectively engage and disengage the harvested aquatic plants.
In a preferred embodiment, the dual paddle wheels each include a drum which is shaped by multiple drum panels closed at both ends and fitted with multiple paddles which extend into the drum, where they are secured by multiple braces. The paddle wheels are rotatably secured to the aquatic harvester and are independently driven.
A growing problem which has become more and more acute around the world is that of the proliferation of aquatic growth and vegetation in inland streams, lakes, rivers and other waterways. This problem is intensified because of the increased use of commercial fertilizers which enter the rivers, lakes and streams as runoff from rainfall or irrigation. This factor, coupled with the depositing of human waste into such waterways, provides a fertile environment for the prolific growth of both floating and bottom-rooted vegetation which chokes the waterways. A controlled quantity of such vegetation is ecologically essential to a balanced, healthy water system, since it acts as a natural cleansing agent by absorbing pollutants in the water and serves as a habitat for a variety of aquatic life. However, when the vegetation reaches a level of overgrowth it can literally destroy the waterway environment and reduce the efficiency of the waterway for commerce or recreation.
There are very few areas in the world which are not faced with excessive aquatic vegetation growth which causes loss of water efficiency through evaporation, loss of storage capacity in reservoirs, reduction of flow rates [from clogging], damage and fouling of pumping systems and loss of recreation and navigation area. Although various chemicals such as herbicides can bring about complete elimination of the many species of weed found in water, they also pollute the water, thereby frequently adding an additional problem. Controlled vegetation harvesting is necessary to facilitate healthy water, in order to leave a selected quantity of plants to provide a filter which absorbs toxic elements and food and shelter for marine life.
There are two primary methods of controlling the over proliferation of aquatic vegetation. The first and most often currently used technique is chemical control by application of herbicides. Herbicides are quick, effective and easily obtainable and at the outset, seem to be currently cost effective. The second most common technique for controlling the growth of aquatic plants and vegetation is by mechanically harvesting the vegetation. Techniques for achieving mechanical harvesting vary from the use of small, open bow boats for manually removing the plants, to larger machines which are designed to cut the plants and load them on the harvesting machine for for future disposal. Mechanical harvesting is a safe method of plant control which results in less impact on the environment than use of herbicides. It is also non-polluting, selective in the amount and type of plant life removed and in the long run, is less costly than the repeated use of herbicides. More importantly, it provides a means for reclaiming the harvested vegetation which can be used for a variety of purposes. The water hycinth is one of the aquatic growth varieties currently clogging many waterways and is being cultivated in some environments as a natural biological filtration system for industrial and sewage waste treatment. Accordingly, it is preferred in most waterway environments not to kill all of the aquatic growth, but instead, to achieve only a selective kill or removal. It has been found that the hycinth plant absorbs both organic and inorganic pollutants, as well as undesirable metals, such as silver, lead, mercury and cadmium. In some applications, this prolific plant is periodically thinned by mechanical harvesting techniques and the vegetation is subsequently recycled and used as a source of methane gas, which is obtained through anaerobic fermentation. Such vegetation can also be converted into organic fertilizers, animal feed and even into food for human consumption.
2. Description Of The Prior Art
As described above, prior art techniques for removing aquatic growth and vegetation from lakes, streams, rivers, reservoirs and other waterways include the use of chemicals and mechanical harvesting. Of the two techniques, mechanical harvesting is more ecologically attractive, since it is non-polluting and can used to selectively remove those varieties and quantities of vegetation desired, in order to leave a selected quantity of vegetation to act as natural filters and shelter for marine life. Typical of the prior art aquatic harvesters in the "Aquatic Harvester" detailed in U.S. Pat. No. 3,698,163 dated Oct. 17, 1972, to Thomas G. Kelpin. This harvester is characterized by multiple pontoons secured to a flat deck member and propelled and steered by an above-the-water air propulsion system. The harvester includes a self-unloading conveyor system, a cutter bar assembly designed for cutting underwater weed growth and a three-phase electrical power system to operate all sub-assemblies. The machine is capable of carrying aquatic vegetation loads in excess of ten tons with a draft of approximately fifteen inches of water. U.S. Pat. No. 3,890,771 dated June 24, 1973, also to Thomas G. Kelpin, discloses an improved aquatic harvester having multiple pontoons secured below the flat deck member, a pickup assembly mounted on the forward end of the craft to collect aquatic material and an above-the-water propulsion and steering system, including an air propulsion unit. The improvement includes pontoon members characterized by at least one closed, integrally formed, buoyant capsule constructed of a plastic material. U.S. Pat. No. 3,847,105 entitled "Aquatic Harvester" and dated Nov. 12, 1974, to Thomas G. Kelpin discloses a similar aquatic harvester, detailing the above-the-water air propulsion system. An "Aquatic Plant Sampler" is described in U.S. Pat. No. 4,177,624 to Thomas G. Kelpin, which device includes an aquatic craft having a plurality of pontoons secured to a flat deck member and propelled and steered by a dual power system, which includes an above-the-water air propulsion mechanism and an underwater drive system. The aquatic plant sampler is further characterized by a sampling bucket fitted with a chain drive cutter system, which bucket is capable of being lowered through a hole provided in the center of the deck to collect aquatic plants, specimens and water bottom samples for analysis, with a view towards controlling such vegetation.
It is an object of this invention to provide a new and improved rake assembly or compactor for organizing, compacting and unloading aquatic growth deposited on the deck of an aquatic harvester and maintaining the aquatic harvester or an even keel during both the loading and the unloading operations.
Another object of the invention is to provide a new and improved paddle wheel system consisting of two paddle wheels mounted at the stern of an aquatic harvester, each of which paddle wheels is independently driven and is characterized by a shaped drum having multiple paddles extending radially through the drum from points of anchor inside the drum and rotatably mounted on the stern of the harvester.
Yet another object of this invention is to provide a new and improved rake assembly or compactor for moving and compacting aquatic vegetation deposited on the deck of an aquatic harvester by a harvesting mechanism, which compactor is characterized by easy maintenance and eliminates the need for a long conveyor bed or large loading apron and is further characterized by a movable carriage driven by a serpentine chain drive system and provided with a pivoted, cylinder-operated rake containing teeth for engaging, compacting and disengaging the harvested aquatic growth.
A still further object of the invention is to provide a new and improved paddle wheel system for an aquatic harvester, which system is characterized by a pair of paddle wheels mounted in side-by-side relationship on the stern of the harvester and individually powered in order to facilitate high maneuverability and efficient operation of the harvester.
A still further object of this invention is to provide a new and improved compactor and paddle wheel system for an aquatic harvester, which compactor includes a carriage mounted on rails on the deck of the aquatic harvester and driven in either of two directions by a serpentine chain drive system, with a rake having multiple teeth fitted therein and pivotally mounted on the carriage for selective engagement, movement and compacting of aquatic growth loaded on the deck by operation of hydraulic cylinders, the paddle wheel system further including a pair of rotating drums, each drum characterized by multiple drum panels closed at both ends and having multiple paddles extending radially and outwardly from a mounting point within the drum, the paddle wheels independently driven, in order to facilitate maximum maneuverability and efficiency in operation of the harvester.